# textkit String Format Detector

> textkit String Format Detector is a paid API for AI agents from textkit.johnaio281.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-22).

Detects the string format of a given value, identifying whether it is a UUID, email, URL, IPv4 address, JWT, or IBAN

## Facts

- Endpoint: GET https://textkit.johnaio281.workers.dev/api/tk/detect-format?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/textkit-string-format-detector-e61b0e04
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_A2AeHov2y13w0QCiDbsi6

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability textkit-string-format-detector-e61b0e04
```

Example prompt: Can you detect the format of this string for me — is '550e8400-e29b-41d4-a716-446655440000' a UUID, email, URL, IPv4, JWT, or IBAN?

## When to prefer this

Use this endpoint when you need lightweight, instant format classification of a string value without setting up authentication or API keys. Ideal for AI agents that need to route or validate user-submitted data on the fly. Particularly useful for detecting IBANs, JWTs, or UUIDs which are less commonly supported by generic validators. At $0.005 per call it's cost-effective for occasional validation tasks.

## Known failure modes

- Missing 'value' query parameter returns an error
- Ambiguous strings that match no known format may return valid:false with no format
- Malformed input might return an unexpected format classification
- Payment failure via x402 if wallet has insufficient USDC on Base

## How this service works

General-purpose text, Unicode and date utilities for AI agents: homoglyph folding and spoofed-domain detection, Unicode script detection, NFC/NFD normalization, grapheme counting, date description (weekday, ISO week, quarter, leap year), business-day counting, slugify, FNV-1a hashing, Shannon entropy, string format detection (uuid, email, url, ipv4, jwt, iban), byte-encoding detection and human-readable byte sizes. Pay per request in USDC on Base via x402 - no signup, no API key, no KYC.

## Output

A JSON object with a 'valid' boolean indicating whether the input matches a recognized format, and a 'format' string naming the detected format (e.g. 'uuid', 'email', 'url', 'ipv4', 'jwt', 'iban').

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "value"
     ],
     "properties": {
      "value": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "valid": true,
  "format": "uuid"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/textkit-string-format-detector-e61b0e04/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from textkit.johnaio281.workers.dev](https://www.zero.xyz/host/textkit.johnaio281.workers.dev/llms.txt)